Search Publications
Monte Carlo predictions of far-infrared emission from spiral galaxies
Bianchi, S.; Davies, J. I.; Alton, P. B.
We present simulations of Far Infrared (FIR) emission by dust in spiral galaxies, based on the Monte Carlo radiative transfer code of \citet*{BianchiApJ1996}. The radiative transfer is carried out at several wavelength in the Ultraviolet (UV), optical and Near Infrared (NIR), to cover the range of the stellar Spectral Energy Distribution (SED). To…
Stellar dynamics observations of a double nucleus in M 83
Genzel, R.; Thatte, N.; Tecza, M.
We report on the discovery of a double nucleus in M 83, based on measurements of the line of sight velocity distribution of stars observed at near infrared wavelengths with the VLT ISAAC spectrograph. We observe two peaks separated by 2\farcs 7 in the velocity dispersion profile of light from late-type stars measured along a slit 0\farcs 6 wide, c…
ISO-SWS spectra of the carbon stars TX Psc, V460 Cyg, and TT Cyg
Jørgensen, U. G.; Hron, J.; Loidl, R.
During our open and discretionary time ISO programs we have observed a number of carbon-rich and oxygen-rich AGB stars. We present here a hydrostatic analysis of 3 carbon rich stars, TX Psc, V460 Cyg, and TT Cyg, which show only modest variability. We identify absorption features of the molecules C_2, CN, CH, CO, CS, HCN, C_2H_2, and C_3 in the th…
New forbidden and fluorescent Fe III lines identified in HST spectra of eta Carinae
Davidson, K.; Johansson, S.; Hartman, H. +4 more
We discuss the origin of eight emission lines in the spectra of gas blobs close to the central star of eta Carinae. The spectra have been obtained with the Goddard High Resolution Spectrograph (GHRS) and the Space Telescope Imaging Spectrograph (STIS) onboard the Hubble Space Telescope. Between 2400 and 2500 Å five narrow lines are identified as n…
Determination of asteroid masses --- I. (1) Ceres, (2) Pallas and (4) Vesta
Michalak, G.
The masses of the three largest asteroids: (1) Ceres, (2) Pallas and (4) Vesta were determined from gravitational perturbations exerted on respectively 25, 2, and 26 selected asteroids. These masses were calculated by means of the least-squares method as weighted means of the values obtained separately from the perturbations on single asteroids. S…
The distance to the nearest star-forming clouds: MBM12 and MBM20
Neuhäuser, R.; Alcalá, J. M.; Covino, E. +2 more
We present high-resolution spectra (R ~ 49,000) of stars that have parallax measurements from the Hipparcos satellite and are projected along the line of sight to the two nearest known star forming clouds to the Sun: MBM12 and MBM20. The spectra were obtained with the FOCES Echelle Spectrograph at the 2.2 meter telescope in Calar Alto, Spain and t…
The morphology of extremely red objects
Cimatti, A.; Daddi, E.; Moriondo, G.
We present a quantitative study of the morphology of 41 Extremely Red Objects (EROs). The analysis is based on deep otical and near-infrared images from the Hubble Space Telescope public archive, and performed by fitting to each galaxy image a PSF-convolved bi-dimensional model brightness distribution. Relying both on the visual inspection of the …
On the origin of the fast solar wind in polar coronal funnels
Mann, G.; Marsch, E.; Hackenberg, P.
Funnels are open magnetic structures connecting the chromosphere with the solar corona ( \cite{Axf97,Mar97,Hac99}). We investigate the stationary plasma flow out of funnels with a flux-tube model. The funnel area function is derived from an analytical 2-D magnetic field model. Since the funnel height is only approximately 15 Mm, the area function …
A spectroscopic study of field BHB star candidates
Cacciari, C.; Bragaglia, A.; Castelli, F. +3 more
New spectroscopic observations are presented for a sample of thirty-one blue horizontal branch (BHB) star candidates that are sufficiently nearby to have reliable proper motions. Comments are given on a further twenty-five stars that have previously been suggested as BHB star candidates but which were not included in our sample. Moderately high-re…
Structure and chemical composition of the silicate dust around OH/IR stars
Dartois, E.; Wiesemeyer, H.; Demyk, K. +2 more
Using a radiative transfer code we have studied the dust shells of the two OH/IR stars IRAS 17004-4119 (OH344.93) and IRAS 17411-3154 (OH357). The ISO-SWS spectra of both sources exhibit deep amorphous silicate absorption bands at 9.8 and 17.5 mu m together with crystalline silicate emission bands at 33.6, 40.5 and 43 mu m. In both sources the 9.8…